To prevent bicycles from being stolen during parking, various locks have heretofore been proposed, the conventional locks being constructed such that when the lock is applied to the front or rear wheel, it prevents the rotation of the wheel.
Such locks, however, pose a problem that they allow a person who is going to commit an illegal act to form a notion that it is possible to break the lock and ride away with the bicycle.
Accordingly, another type of antitheft device different from a lock may be contemplated which is adapted to lock the saddle itself in an unridable form which gives a notion of "unridableness", thereby preventing theft.
Even if such antitheft device which locks the saddle in an unridable form is to be employed, however, the legitimate bicycle owner has to perform three operations in parking his bicycle; erecting the stand, locking the thus-erected stand or applying a separate lock, and locking the saddle itself in an unridable form.